1. Technical Field
Disclosed is a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS), in which a preamplifier is installed as nearest to an ion cyclotron resonance (ICR) trap as possible at a detector part in the mass spectrometer and thermal noise generated at the preamplifier is minimized by means of a cryo-cooling system to increase a signal-to-noise ratio of ion detection signals such that an ultra-low amount of specimen can be detected, which was impossible in the related art.
2. Description of the Related Art
Generally, an existing preamplifier that measures signals of a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) as shown in FIG. 1 is used for amplifying an input signal by fine image current induced to an electrode surrounded by ions confined by high magnetic field and electric field, and it gives a great influence on a signal-to-noise ratio of the entire ion signals. In particular, thermal noise should be decreased to improve the signal-to-noise ratio.
However, in case a preamplifier used at a normal temperature is cooled to a low temperature to minimize thermal noise generally existing at a normal temperature, the preamplifier may not be operated normally as a high signal-to-noise ratio signal detection device since the design and parts of the preamplifier are optimized for the normal temperature. In addition, due to the insulation from other parts that should not be cooled, it is difficult to cool the preamplifier to a desired temperature. Also, the preamplifier should be installed together with a vacuum device such that the thermal isolation device may keep a pressure difference between the outside under an atmospheric pressure and an ultra high vacuum region where electric circuits to be cooled are located.